From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Tests carried out on C.F. sparking plug electrodes to determine the variation of the transmission coefficient.
| Identifier | ExFiles\Box 58\2\ Scan128 | |
| Date | 14th June 1934 guessed | |
| F.I.M.A.C. MILANO REPORT ON TESTS CARRIED OUT ON ELECTRODES C.F. Sparking Plugs. ------- These tests were carried out by Messrs. FIMAC in their workshops, to determine the variation value of the transmission coefficient of the F.C. sparking plugs made by them. The said values are determined for the two extreme limits of operation, namely, for a hot plug (detached pin) and a cold plug (contact pin). A calorimeter fitted up as shown in the attached sketch, was used in the tests, whose results are given in the following report. During the tests the oil, which was the heating element of a mercury bath in which the head of the electrode was placed, circulated in the radiator system and was kept at a constant temperature of 216°, which corresponded to one of 150° for the bath. Determination of the time required to bring the calorimeter's water from 30 to 35°, was taken as a basis of the tests in the aforesaid conditions, with a room temperature of about 20°. The single component parts of the calorimeter, including those of the electrode placed in same, were weighed and the specific heat of the calorimeter was calculated. It was found to be 0,0778. As all the tests took place with a temperature jump of 5°, the quantity of heat given to the calorimeter was always: Q = 0,0778 x 5 = 0,389. The tests that took place were as follows: 1.- Determination of to what extent the calorimeter was indirectly heated by the underlying heater without the electrode (but a body of specific heat equal to the electrode taken away, was contained | ||